Definitions for GIS terms related to operations such as analysis, GIS modeling and web-based GIS, cartography, and Esri software.
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The height or vertical elevation of a point above a reference surface. Altitude measurements are usually based on a given reference datum, such as mean sea level.
The height above the horizon, measured in degrees, from which a light source illuminates a surface. Altitude is used when calculating a hillshade, or for controlling the position of a light source in a scene.